Help me out with 285's.. (questions)

F

Falls

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As soon as I can find time and FIND 1" OR 1.5" rear springs I'll get my lift on. It looks like I will need to go to 285's so looks proportionate .

Why do some people have to trim the heck out of their truck and others don't have an issue ? Is this simply because of the wheels ...offset/backspace they choose ??

Ive seen one guy on here have them on before he got lifted . How could that be if so many have issues ?

Would I rub at all with stock wheels (TE) and a 2.5" front lift ? I do not want to push the CO's to the 3"+ max ( Toytec kit )

I am also concerned about gas milage a little , but not to bad since I didn't buy this to get good milage anyway , BUT power robbing tires (285's) is a concern since I feel this thing lack power anyway , but then again I came from a V8 so.....
 
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Larger circumference tires effectively change your final drive ratio but what a lot of people don't realize is the bigger hit on gas milage comes from adding unsprung weight by putting on heavier tires. Heavier is not always better depending on what you are going to do.
 
My freind put 285s on his 09 4.0 Tacoma and has regretted it ever since. He lost 2 mpg and says it is constantly hunting for the right gear on the slightest grade. It just took the fun out of driving it. They take a lot of power to turn. He wishes he would have only went to a 275.
 
I just put 285 Duratracs on mine and there was a power loss but not that bad. I can still pass people just fine. I havent felt it hunting for gears either. Im not sure why i had to trim the heck out of the inner fenders but i did. i think it was a combo of the 1.5" wheelspacers and the aggressive side lug of the Duratracs. The agressive look was worth it to me though.
 
I had 285's on my 08 Tacoma and yeah lost quite a bit of power. I then had Doug Thorley headers installed and an AFE intake. Gained some of the power back but I still got terrible mileage.

I did just go to Vegas, Up and down hills 300 mile trip both ways and the 4Runner did really well for having my Destination M/T 285's on it. I got 18.75 mpg there and 19 mpg back. That's actual calculations, not what the in dash computer showed. In city alone I average 13.5-14, thats according to the dash computer. So real world might be a little better. City/hwy mix 15-16mpg. I keep about 40 psi cold in them always which turns into 45psi warm.

If you go with 17X8 with 4.5" of backspacing, you will not have to trim much. Just move the front piece of liner forward and maybe remove the mud flap. I rub slightly when turning full lock backwards. It sounds terrible inside but outside, you can hardly hear the rubbing. And its only rubbing my mud flap which I chose to keep on. Thats at 2-2.5" of approx. lift up front with OEM Control Arms.
 
I will say that when mine did rub it was only at certain times when backing up and turning. There was no rub during normal straight line driving or turning, but when it did rub it was loud and annoying, so i cut off all of the offending plastic. Th eplastic i cut was essentially the inner fender in front of the tire all the way up to the first plastic clip that holds the inner fender onto the outer fender. About 6-8" worth of inner fender.
 
Brad2064 said:
I just put 285 Duratracs on mine and there was a power loss but not that bad. I can still pass people just fine. I havent felt it hunting for gears either. Im not sure why i had to trim the heck out of the inner fenders but i did. i think it was a combo of the 1.5" wheelspacers and the aggressive side lug of the Duratracs. The agressive look was worth it to me though.
Click to expand...

I do not know where Brad2064 lives but if it is flat country then it may not be
as bad but here in the mountains in Arizona taller tires/ heavier tires are noticable. It was noticable on my V8 4runner just going from 265/65/17 stock tires to 265/70/17 all terrain tires. It just saps a little power away and takes some of the responsiveness and fun out of driving. If you just want it to look better then 285s are for you.
 
Taller tires could actually give you better gas milage depending on how much freeway driving and what sort of tread pattern you went with. Most people don't adjust the speedometer after increasing tire sizes so it skewes the readings since you actually covered more miles than you are calculating. In city driving, yes they suck as the engine is working much harder to get up to speed, but for highway cruising after you've gotten up to speed and at low RPM's you should get better MPG's with the taller tire.
 
Will733 said:
Taller tires could actually give you better gas milage depending on how much freeway driving and what sort of tread pattern you went with. Most people don't adjust the speedometer after increasing tire sizes so it skewes the readings since you actually covered more miles than you are calculating. In city driving, yes they suck as the engine is working much harder to get up to speed, but for highway cruising after you've gotten up to speed and at low RPM's you should get better MPG's with the taller tire.
Click to expand...

I just gotta jump in here with a little physics. :frisky:

If you go up in tire diameter from 32 to 33 inches without recalibrating your speedometer/odometer, you will have two effects.

1. The simple geometric change in distance traveled is 33/32 = 1.031. That's 3.1 percent.

2. You will want to travel faster, because when your speedometer says 75MPH you will really be doing 77.3 MPH. Since the aerodynamic force goes as the square of the speed, the difference here is 77.3 squared /75 squared = 1.062. That's another 6.2 percent.

Add them up, you get almost 10 percent difference just by not recalibrating your speedometer. If you were getting 20 MPG before, now you'll see 18 MPG.

Now, if you put a three inch lift on your 4Runner, you're adding approximately another 5 percent on the area of the hole you're punching through the air. That's another 1 MPG, so you're down to 17 MPG.

According to the article cited in Four Wheeler Magazine, the difference in tire rolling resistance (due to carcass, lugs, rubber compound and thickness) can easily be 2 MPG (and that's if you increase your tire pressure appropriately). So now you're down to 15 MPG.

If you made it this far, thanks for your patience. I just had to do it.:thanks:
 
rlumpy said:
I just gotta jump in here with a little physics. :frisky:

If you go up in tire diameter from 32 to 33 inches without recalibrating your speedometer/odometer, you will have two effects.

1. The simple geometric change in distance traveled is 33/32 = 1.031. That's 3.1 percent.

2. You will want to travel faster, because when your speedometer says 75MPH you will really be doing 77.3 MPH. Since the aerodynamic force goes as the square of the speed, the difference here is 77.3 squared /75 squared = 1.062. That's another 6.2 percent.

Add them up, you get almost 10 percent difference just by not recalibrating your speedometer. If you were getting 20 MPG before, now you'll see 18 MPG.

Now, if you put a three inch lift on your 4Runner, you're adding approximately another 5 percent on the area of the hole you're punching through the air. That's another 1 MPG, so you're down to 17 MPG.

According to the article cited in Four Wheeler Magazine, the difference in tire rolling resistance (due to carcass, lugs, rubber compound and thickness) can easily be 2 MPG (and that's if you increase your tire pressure appropriately). So now you're down to 15 MPG.

If you made it this far, thanks for your patience. I just had to do it.:thanks:
Click to expand...

The odometer being off has been discussed on this forum before and many people including myself have verified the mpg lose using a gps to track the miles.
 
rlumpy said:
I just gotta jump in here with a little physics. :frisky:

If you go up in tire diameter from 32 to 33 inches without recalibrating your speedometer/odometer, you will have two effects.

1. The simple geometric change in distance traveled is 33/32 = 1.031. That's 3.1 percent.

2. You will want to travel faster, because when your speedometer says 75MPH you will really be doing 77.3 MPH. Since the aerodynamic force goes as the square of the speed, the difference here is 77.3 squared /75 squared = 1.062. That's another 6.2 percent.

Add them up, you get almost 10 percent difference just by not recalibrating your speedometer. If you were getting 20 MPG before, now you'll see 18 MPG.

Now, if you put a three inch lift on your 4Runner, you're adding approximately another 5 percent on the area of the hole you're punching through the air. That's another 1 MPG, so you're down to 17 MPG.

According to the article cited in Four Wheeler Magazine, the difference in tire rolling resistance (due to carcass, lugs, rubber compound and thickness) can easily be 2 MPG (and that's if you increase your tire pressure appropriately). So now you're down to 15 MPG.

If you made it this far, thanks for your patience. I just had to do it.:thanks:
Click to expand...

Good explanation. I was gonna but I could not find the document I wrote to explain this exact same thing several times over on the Honda Ridgeline forum. Good job.
 
IMO.....If you ran the stock Duelers/Dunflops tires in 265/70 and then ran them in 285/70 you would only see a little drop in true gas mileage,not what the gauges say as they will be off.

As Will733 stated, if you ran them on the highway at a speed that optimized the gearing/gas mileage(not 60-65mph like it is now for the 265's) for the 285/70 taller tire the only difference would be the heavier weight of the 285 .

Now of course changing to a AT or MT tire and a lift changes the whole ballgame.
The oil companies and their Billion dollar a day profits are behind it all!
 
I would just rather stick to stock size , but we'll see .... I will have to change to a smaller lift so it does not look out of place , but I do plan on wider aftermarket rims 17x8's . I may just have to do some small spacer lift w/Bilstiens to keep think proportioned and still have a better shock. . sucks for me !!!!

Yes an AT tire would be a given , I swapped tires to an AT asap when I go my truck. The lift will also be a milage killer too .
 
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